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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 475-486页

作者： Essam B.moustafa Mohammed A.Taha Mechanical Engineering Departments Faculty of EngineeringKing Abdulaziz UniversityJeddah 21589Saudi Arabia Solid State Physics Department National Research CentreEl Buhouth St.Dokki12622 GizaEgypt

Nano-sized silicon carbide(SiC:0wt%,1wt%,2wt%,4wt%,and 8wt%)reinforced copper(Cu)matrix nanocomposites were manufactured,pressed,and sintered at 775 and 875℃in an argon atmosphere.X-ray diffraction(XRD)and scanning electron microscopy were performed to characterize the microstructural *** density,thermal expansion,mechanical,and electrical properties were *** analyses showed that with increasing SiC content,the microstrain and dislocation density increased,while the crystal size *** coefficient of thermal expansion(CTE)of the nanocomposites was less than that of the Cu *** improvement in the CTE with increasing sintering temperature may be because of densification of the ***,the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures,where the microhardness and apparent strengthening efficiency of nanocomposites containing 8wt%SiC and sintered at 875℃were 958.7 MPa and 1.07 vol%^(−1),*** electrical conductivity of the sample slightly decreased with additional SiC and increased with sintering *** prepared Cu/SiC nanocomposites possessed good electrical conductivity,high thermal stability,and excellent mechanical properties.

关键词： copper matrix nanocomposites silicon carbide coefficient of thermal expansion elastic moduli electrical conductivity mechanical alloying

Isolation, purification and structure elucidation of three newbioactive secondary metabolites from Streptomyces lividans AM

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BIOCelL 2021年第5期45卷 1263-1271页

作者： MOHAMMAD el-METWALLY MAMDOUH ABDel-MOGIB MANAL elFEDAWY GAAD SOHSAH AHMED REZK MAHMOUD moustafa MOHAMED SHAABAN Botany and Microbiology Department Faculty of ScienceDamanhour UniversityDamanhour22511Egypt Chemistry Department Faculty of ScienceMansoura UniversityEl-Mansoura35516Egypt Bioprocess Development Department Genetic Engineering and Biotechnology Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab CityAlexandria21934Egypt Biology Department College of ScienceKing Khalid UniversityAbha9004Saudi Arabia Chemistry of Natural Compounds Department Division of Pharmaceutical IndustriesNational Research CentreDokki-Cairo12622Egypt Organic and Bioorganic Chemistry Department of ChemistryBielefeld UniversityBielefeld33615Germany

Microorganisms are a huge mine of bioactive metabolites,and actinomycetes are one of the very active groups in this *** this article,we are concerned about the full taxonomical characterization of Streptomyces lividans AM,isolated from Egyptian *** isolate produced three new bioactive metabolites,namely:1-Nona-decanoyl,4-oleyl disuccinate(1),filoboletic acid;(9Z,11E)-8,13-dihydroxy octadeca-9,11-dienoic acid(2),and sitosteryl-3β-D-glucoside(3).Extensive 1D and 2D NMR and HR-mass spectrometry were used to elucidate the structures of the three ***,ten known compounds were also *** antimicrobial activity of the producing organism and newly reported compounds(1–3)was investigated against a selected group of pathogenic microorganisms.A full taxonomical characterization of the strain was described as well.

关键词： Bioactive metabolites Streptomyces sp. Taxonomy Biological activity

铁对粉末冶金法制备铝基复合材料微观组织和力学性能及磁学性能的影响(英文)

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Transactions of Nonferrous Metals Society of China 2015年第1期25卷 46-53页

作者： A.FATHY Omyma el-KADY moustafa M.M.MOHAMMED Department of Mechanical Design and Production Engineering Faculty of Engineering Zagazig University Powder Metallurgy Division Manufacturing DepartmentCentral Metallurgical Research and Development Institute Department of Production Technology Faculty of Industrial Education Beni-Suef University

研究铁对粉末冶金法制备铝基复合材料微观组织、力学性能及磁学性能的影响。利用机械混合制备含0,5%,10%和15%Fe(质量分数)的铝基复合材料。Al-Fe混合粉末经压制后在真空炉中600°C烧结1 h。XRD结果表明:在含有5%和10%Fe的试样中只有Fe... 详细信息

研究铁对粉末冶金法制备铝基复合材料微观组织、力学性能及磁学性能的影响。利用机械混合制备含0,5%,10%和15%Fe(质量分数)的铝基复合材料。Al-Fe混合粉末经压制后在真空炉中600°C烧结1 h。XRD结果表明:在含有5%和10%Fe的试样中只有Fe和Al的衍射峰,而含有15%Fe的试样中则存在Al和Al13Fe4的衍射峰。实验结果表明:随着Fe含量的增加,材料的致密度和导热性变差。复合材料中的Fe可以提高其强度和硬度。材料的强化机制包括基体的晶粒细化,Fe颗粒的均匀分布以及Al13Fe4金属间化合物的形成。含有5%Fe试样的磁化强度为0.3816×10-3A·m2/g,对于含有10%Fe的试样,其磁化强度增加至0.6597×10-3A·m2/g,而对于含有15%Fe试样,其磁化强度降低至0.0702×10-3A·m2/g。这是由于在高铁试样中形成了反磁性的Al13Fe4金属间化合物导致磁化强度降低。

关键词： Al-Fe复合材料粉末冶金微观组织力学性能磁学性能

New Polymer Syntheses Part 60: A Facile Synthetic Route to Polyamides Based on Thieno[2,3-b]thiophene and Their Corrosion Inhibition Behavior

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Chinese Journal of Polymer Science 2018年第7期36卷 835-847页

作者： Kamal I.Aly Amr H.moustafa Essam K.Ahmed Hany M.Abd el-lateef Mohamed Gamal Mohamed Sahar M.Mohamed Polymer Research Lab Chemistry Department Faculty of Science Assiut University Chemistry Department Faculty of Science Sohag University Chemistry Department Faculty of Science Minia University Chemistry Department College of Science King Faisal university

Polyamides containing thieno[2,3-b]thiophene moiety were prepared via a simple polycondensation reaction of the diaminothieno[2,3-b]thiophene monomer la with different kinds of diacid chlorides （including oxalyl, adipoyl, sebacoyl, isophthaloyl, terephthaloyl, 4,4＇-azodibenzoyl, 3,3＇-azodibenzoyl, p-phenylene diacryloyl） in the presence of LiC1 and NMP as a solvent through lowtemperature solution polycondensation. The chemical structures of model compound and synthesized polyamides were confirmed by FTIR, nuclear magnetic resonance spectroscopy （including 1 H-NMR and 13 C-NMR） and elemental analysis. In addition, the thermal stability, crystallinity structure and surface morphology of synthesized polyamides were characterized via thermogravametric analysis （TGA）, wide-angle X-ray diffraction analysis （WAXD） and scanning electron microscopy （SEM）. Also, the corrosion inhibition behavior of selected examples ofpolyamides was investigated; the inhibitive effect of the investigated polymers for carbon steel in 1.0 mol＇L-1 HCI was studied using potentiodynamic polarization （PDP） and electrochemical impedance spectroscopy （EIS） methods. PDP results displayed that the polyamides containing thieno[2,3-b]thiophene moiety can be as mixed-type inhibitors. The inhibition efficiency （P, %） was found to be in the range from 67.13% to 96.01%. There is an increase in P by the synthesized polymers in comparison to the starting monomer. The adsorption of these polymers was found to obey Langmuir adsorption isotherm.

关键词： Thieno[2 3-b]thiophene Polymer synthesis Thermal properties Industrial applications Corrosion inhibition

Involvement of Quebracho tannins in diet alters productive and reproductive efficiency of postpartum buffalo cows

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Animal Nutrition 2019年第1期5卷 80-86页

作者： Sobhy M.A.Sallam Marwa F.A.Attia Adel N.M.Nour el-Din Samir Z.el-Zarkouny Adel M.Saber Hani M.el-Zaiat moustafa M.Zeitoun Department of Animal and Fish Production Faculty of AgricultureAlexandria University Animal Production Research Institute Agricultural Research CenterDokki

This study was conducted to investigate the effects of 10 weeks supplementation of Quebracho tannins(QT; 0 [control], 100 [QT100] or 200 g/[cow$d] [QT_(200)]) to 30 multiparous postpartum buffalo cows(10 cows per group) on milk yield and composition, blood metabolites and reproductive *** of QT100 had no significant effect on milk yield, whereas QT_(200) decreased(P els decreased(P eld, but no significant effects were found on percentages of milk fat and protein. Contrariwise, yields of milk fat, lactose and milk protein were decreased(P eld were decreased(P < 0.05) with QT100 supplementation. Moreover, QT tended to numerically reduce total number of ovarian follicles, number of small follicles, peripheral progesterone concentration and conception rate. Supplementation of QT_(200) numerically increased number of large follicles, mean diameter of large follicle, number and diameters of corpora lutea. The inclusion of QT_(200) shortened days open(DO) and decreased number of services per ***, QT did not show significant effects on serum total protein, albumin, globulin, glucose,cholesterol and triglycerides concentrations. Supplementation of QT100 caused an increase(P < 0.05) of serum urea compared with that in control and QT_(200) groups. Generally, QT decreased(P < 0.05) serum creatinine concentration. Therefore, the supplementation of a commercial QT to early lactating Egyptian buffalo cows displayed negative consequences on their productive and reproductive performances.

关键词： Buffalo Tannins Milk traits Blood metabolites Ovarian follicles Conception rate

Constraints of Mantle and Crustal Sources Interaction during Orogenesis of Pre-and Post-collision Granitoids from the Northern Arabian-Nubian Shield:A Case Study from Wadi el-Akhder Granitoids,Southern Sinai,Egypt

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1527-1550页

作者： moustafa M.MOGAHED Khaled M.ABDelFADIL Geology Department Faculty of ScienceBenha UniversityBenha 13518Egypt Geology Department Faculty of ScienceSohag UniversitySohag 82524Egypt

The Egyptian older and younger granitic rocks emplaced during pre-and post-collision stages of Neoproterozoic Pan-African orogeny,respectively,are widely distributed in the southern Sinai Peninsula,constituting 70% of the basement *** Wadi el-Akhder,southwestern Sinai,is a mountainous terrain exposing two granitoid suites,namely the Wadi el-Akhder Older Granites(AOG)and the Homra Younger Granites(HYG).The AOG(granodiorites with subordinate tonalite compositions)have geochemical characteristics of medium-K calc-alkaline,metaluminous to mildly peraluminous granitoids formed in an island-arc environment,which are conformable with well-known Egyptian older granitoids rocks,whereas the HYG display calc-alkaline to slightly alkaline nature,peraluminous syeno-,monzogranites and alkali feldspar granites matching well those of the Egyptian younger *** respect to the AOG granitoids,the HYG granites contain lower Al_(2)O_(3),FeO^(*),MgO,MnO,CaO,TiO_(2),Sr,Ba,and V,but higher Na_(2)O,K_(2)O,Nb,Zr,Th,and *** AOG are generally characterized by enrichment in LILE and LREE and depletion in HFSE relative to N-MORB values(e.g.,negative Nb and Ta anomalies).The geochemical features of the AOG follow assimilation-fractional crystallization(AFC)trends indicative of extensive crustal contamination of magma derived from a mantle *** chemical characteristics of the AOG are remarkably similar to those of subduction-related granitoids from the ArabianNubian Shield(ANS).The compositional variations from monzogranites through syenogranites to alkali feldspar granite within HYG could not be explained by fractional crystallization *** the whole-rock composition of the HYG to melts generated by experimental dehydration melting of meta-sedimentary and magmatic rocks reveals that they appear to be derived by extended melting of psammitic and pelitic metasediments,which is similar to the most of younger granitic suites in the ANS.

关键词： older and younger granitoids mantle-crust interaction assimilation-fractional crystallization(AFC) southern Sinai Arabian-Nubian Shield

Consensus statement on the epidemiology,diagnosis,prevention,and management of cow's milk protein allergy in the Middle East:a modified Delphi-based study

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World Journal of Pediatrics 2021年第6期17卷 576-589页

作者： moustafa A.el-Hodhod Mortada H.F.el-Shabrawi Ahmed AIBadi Ahmed Hussein AM Almehaidib Basil Nasrallah Ebtsam Mohammed AIBassam Hala el Feghali Hasan M.Isa Khaled Al Saraf Maroun Sokhn Mehdi Adeli Najwa Mohammed Mousa Al-Sawi Pierre Hage Suleiman Al-Hammadi Department of Pediatrics Faculty of MedicineAin Shams UniversityCairoEgypt Faculty of Medicine October 6 UniversityGizaEgypt Faculty of Medicine Cairo UniversityCairoEgypt International Pediatric Association(IPA) MarengoUSA International Society of Tropical Pediatrics(ISTP) ManilaPhilippines DRC Hospital MuscatOman Al Amiri and Al Adan Hospitals KuwaitKuwait Pediatric Gastroenterology Department of PediatricsKing Faisal Specialist Hospital and Research Center RiyadhRiyadhSaudi Arabia American Hospital Dubai DubaiUnited Arab Emirates Nutrition Service Department King Faisal Specialist and Research Center RiyadhRiyadhSaudi Arabia CHU Notre Dame de Secours ByblosLebanon Pediatric Department Salmaniya Medical ComplexManamaBahrain Pediatric department Arabian Gulf UniversityManamaBahrain Pediatrics Department Dar Al Shifa HospitalKuwaitKuwait Pediatric Gastroenterology Hepatologyand Nutrition DepartmentSaint George University Medical CenterUniversity of BalamandBeirutLebanon Sidra Medicine DohaQatar Department of Pediatrics Doctor Sulaiman Alhabib Medical GroupAlrryan BranchRiyadhSaudi Arabia Pediatric Pulmonology and Allergology University of BalamandBeirutLebanon College of Medicine Mohanuned Bin Rashid University of Medicine and Health SciencesBuilding 14505055 DubaiUnited Arab Emirates

Background This study aimed to develop an expert consensus regarding the epidemiology,diagnosis,and management of cow’s milk protein allergy(CMPA)in the Middle *** A three-step modified Delphi method was utilized to develop the *** specialized pediatricians participated in the development of this *** statement was considered a consensus if it achieved an agreement level of>80%.Results The experts agreed that the double-blind placebo-controlled oral challenge test(OCT)should be performed for 2-A weeks using an amino acid formula(AAF)in formula-fed infants or children with suspected ***-fed infants with confirmed CMPA should be offered a therapeutic *** panel stated that an extensively hydrolyzed formula(eHF)is indicated in the absence of red flag *** the same time,the AAF is offered for infants with red flag signs,such as severe anaphylactic *** panel agreed that infants on an eHF with resolved symptoms within 2-4 weeks should continue the eHF with particular attention to the growth and nutritional *** the other hand,an AAF should be considered for infants with persistent symptoms;the AAF should be continued if the symptoms resolve within 2-4 weeks,with particular attention to the growth and nutritional *** cases with no symptomatic improvements after the introduction of an *** measures should be *** panel developed a management algorithm,which achieved an agreement level of 90.9%.Conclusion This consensus document combined the best available evidence and clinical experience to optimize the management of CMPA in the Middle East.

关键词： Consensus Cow's milk protein allergy Infant formula Middle East Milk hypersensitivity

新型包覆Pb纳米粒子液相色谱-串联质谱法用于鉴定沙特阿拉伯原油中的含氧化合物（英文）

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色谱 2018年第4期36卷 362-369页

作者： Nagy E.moustafa Kout el-Kloub Fars MAHMOUD Egyptian Petroleum Research Institute Department of Chemistry Women's College for ArtsScience and EducationAin Shams University

Saudi Arabian crude oil is a super complex mixture and,up to now,there has been little research into its heteroatom-containing ***,oxygenated compounds(OCs)were isolated from Saudi Arabian oil using a Pd nanoparticle exchange complex,which formed between the nano-Pds and the oxygenated ***,polycyclic aromatic sulphur heterocycles(S-PAHs)are separated from petroleum oil via the same *** obtained results reveal that all the OC formulations with S-PAHs can be separated from the pre-isolated aromatic fraction of crude oil via this approach.S-PAHs are mixtures of benzothiophene and dibenzothiophene *** isolated OCs are composed mainly of hydroxyl *** liquid chromatography(LC)/electrospray ionization(ESI)in positive ion mode ESI(+)/tandem mass spectrometry(MS/MS)technique was used to assign the molecular weight distribution and identify the isolated *** LC/ESI(+)-MS/MS technique differentiates S-PAHs and OCs using protonated ***,LC/ESI(+)-MS/MS can be used to assign molecular weight distributions for both the groups as a single ***/MS in precursor ion mode was used for the immediate identification of the target S or O analytes.

关键词： liquid chromatography(LC) tandem mass spectrometry(MS/MS) Pd nanoparticles crude oil oxygenates

Generalization of Some Problems with <i>s</i>-Separation

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Applied Mathematics 2015年第1期6卷 1-6页

作者： Beih el-Sayed el-Desouky Mohamed moustafa Gad Shimaa el-Eraqy Department of Mathematics Faculty of Science Mansoura University Mansoura Egypt

In this article we apply and discuss el-Desouky technique to derive a generalization of the problem of selecting k balls from an n-line with no two adjacent balls being s-separation. We solve the problem in which the separation of the adjacent elements is not having odd and even separation. Also we enumerate the number of ways of selecting k objects from n-line objects with no two adjacent being of separations m, m + 1, …, pm, where p is positive integer. Moreover we discuss some applications on these problems.

关键词： Probability Function ss-Separation s-Successions n-Line n-Circle

Use of Geomatic Approaches to Characterize Arqa River Basin: A Typical Coastal Lebanese River

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Open Journal of Modern Hydrology 2015年第3期5卷 45-57页

作者： Abdulrahim Ibrahim moustafa Al Hajj Mhamad el Hage Department of Geography (GISRS Lab) Lebanese University Tripoli Lebanon Centre for Language and Communication Studies Lebanese University Beirut Lebanon Department of Geography (GISRS Lab) and Department of Civil Engineering Lebanese University Tripoli Lebanon

Water resources in Lebanon are one of the major threatened natural resources, since they spread on different geographic locations creating a network of permanent and temporary watercourses that govern the socio-economy and livelihood. However, lately, these watercourses, and certainly the rivers and streams, are witnessing unfavorable impacts that make them with less benefit and use. In addition, most of the Lebanese river basins have not been characterized due to the newly physical challenges of climate change and the human interference. Hence, characterization of the Lebanese river basins must be obtained in order to monitor the changing of physical and anthropogenic parameters. This can help for better conservation and adaptation approaches, notably for climate change. Arqa River, a coastal Lebanese river in North Lebanon is a typical example. In this study, Arqa River basin and the occupied streams among it have been studied using new advanced geomatic techniques. These techniques are based on the treatment of digital geo-spatial data in systematic approaches. ArcGIS is the software which is used to elaborate and manipulate (data interrelation, measures, overlapping, ordering, etc.) the geo-spatial data. Thus, the geometric and morphometric analysis were obtained for the river catchment and the existing tributaries. This will be a primary tool for further applications including water resources management in the river system. This can be utilized in the execution of dams, mountain lakes, man-made channels and in mapping flood-prone areas. In addition, the obtained characterization of this basin will be helpful in mapping erosion processes and estimation of the infiltration capacity, plus monitoring surface water flow. It is a typical approach of analysis that can be applied for the rest of Lebanese river systems in order to attain a better water resources management. This study shows that the use of geomatic techniques is a very helpful tool in the study of basin

关键词： Geomatic Remote Sensing GIS DEM Morphometry